1. A subtraction expression that we can use to evaluate and find the depth of the submersible at 2:16 p.m. is y = -z - x, and the solution shows that the submersible is 220 feet below sea level at 2:16 p.m.
2. A subtraction expression that we can use to evaluate and find the depth of the submersible at 2:17 p.m. is y = -z - x, and the solution shows that the submersible is 215 feet below sea level at 2:17 p.m.
The starting position of the submersible at 2:15 p.m. = -40 feet
Let the previous position of the submersible = -z
Let the position of the submersible at any time = y
Let the depth covered at the time = x
Equation:
y = -z - x
At 2:16 p.m. when x = 180 feet lower:
y = -40 - 180
y = -220 feet
2:17 p.m. when the submersible went 175 feet lower than at 2:16 p.m.:
y = -220 - 175
y = -395 feet
Complete Question:
A submersible is a type of underwater vessel. Suppose a submersible starts at a depth of 40 feet below sea level, represented by - 40 feet. The table shows the submersible change in depth from one minute to the next.
Time and Depth of Submersible
2:15 p.m. 2:16 p.m. 2:17 p.m. 2:18 p.m.
-40 feet 180 feet lower 175 feet lower 185 feet lower
1. Write and evaluate a subtraction expression to find the depth of the submersible at 2:16 p.m.
2. Write and evaluate a subtraction expression to find the depth of the submersible at 2:17 p.m.